I just had fault codes for high DPF outlet temp and unusual doser valve pressure. I monitored the temp during regen to 1077deg and the doser valve static was at 7lbs, and between 17.5 to 24.5 during regen. what is the spec for the fuel pressure the doser valve. the regen was sucessful. what else should I look for to log these codes thx.

hey popskull... do you have the codes so you can post them. I will post some Detroit regen information here in the next couple of days. There is a code that does come up and you are suppose to watch 2 pressures in the data monitor. If there is less that 35 psi differance you are to replace the fuel shut off valve. I will post details later.

Here is a code I see on 60S this code will most of the time be inactive. SPN 3556 FMI 1 When following the troubleshooting steps I make it step 7. - 2. and end up replacing the Doser Block Assembly. These step will have you watch Doser pressure and fuel compensation pressure. This somewhat applies to your question about fuel pressure but also applies to a unit that will not get up to temperature during a regen.

a. If the resistance is out of specification replace DOC Outlet Temperature Sensor, refer to "3.1.2 TEMPERATURE SENSOR REMOVAL" , go to step 8 . b. If the resistance is within specification, go to step 5 .

Thx... By the specs you listed I see that the fuel pressure was low. The same unit was seen just this week and the code still has not returned but I anticipate that it is teetering on the edge of failure and the information posted will save me wasted steps.

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